If your thinking about replacing your boiler there is probably a million and one questions that you need answering, such as, what type of boiler do I need, how much will it cost me to replace a boiler, do you go for a back boiler or a combi. Hopeful I can help with these questions and make purchasing a need boiler simpler for you. In answer the first question I highlighted above most households have some sort of combination boiler fitted, back boilers are no longer deemed to be very economical. The cost of a new back boiler varies £600-£1000+ depending on the make and model. Once you have found a boiler that suits your needs you will need to find a good gas fitter, just make sure they have all the right qualifications and are listed on the gas safe register.